v2.4.1.9

RELATED-PARTY TRANSACTIONS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		0 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Aug. 30, 2014 item	Apr. 15, 2014	Dec. 31, 2014	Jun. 30, 2014
Related-party transactions
Principal repayments		$ 686us-gaap_RepaymentOfNotesReceivableFromRelatedParties
Investment into the entity controlled by a related party	20,151us-gaap_EquityMethodInvestments				17,416us-gaap_EquityMethodInvestments
Income (loss) from equity method investment	2,865us-gaap_IncomeLossFromEquityMethodInvestments	(1,220)us-gaap_IncomeLossFromEquityMethodInvestments
Aircraft lease entered into during August 2014
Related-party transactions
Number of lessees of aircraft (other than the Company), including related party			2mc_NumberOfLesseesOfAircraftIncludingRelatedPartyExcludingReportingEntity / us-gaap_RelatedPartyTransactionAxis = mc_AircraftLeaseEnteredIntoDuringAugust2014Member
Manager | Aircraft lease entered into during April 2010
Related-party transactions
Expenses		401us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty / us-gaap_RelatedPartyTransactionAxis = mc_AircraftLeaseEnteredIntoApril2010Member / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAndCompanyManagerLLCMember
Manager | Aircraft lease entered into during April 2014
Related-party transactions
Aircraft lease term				10 years
Manager | Aircraft lease entered into during August 2014
Related-party transactions
Expenses	312us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty / us-gaap_RelatedPartyTransactionAxis = mc_AircraftLeaseEnteredIntoDuringAugust2014Member / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAndCompanyManagerLLCMember
Number of lessess of aircraft who are a related party			1mc_RelatedPartyTransactionNumberOfLesseesOfAircraft / us-gaap_RelatedPartyTransactionAxis = mc_AircraftLeaseEnteredIntoDuringAugust2014Member / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAndCompanyManagerLLCMember
Employees | Unsecured promissory notes
Related-party transactions
Unsecured promissory notes from employees	119us-gaap_NotesReceivableRelatedParties / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_NotesReceivableMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_EmployeesMember				119us-gaap_NotesReceivableRelatedParties / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_NotesReceivableMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_EmployeesMember
Interest rates (as a percent)	4.00%us-gaap_RelatedPartyTransactionRate / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_NotesReceivableMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_EmployeesMember				4.00%us-gaap_RelatedPartyTransactionRate / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_NotesReceivableMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_EmployeesMember
Principal repayments	0us-gaap_RepaymentOfNotesReceivableFromRelatedParties / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_NotesReceivableMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_EmployeesMember	686us-gaap_RepaymentOfNotesReceivableFromRelatedParties / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_NotesReceivableMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_EmployeesMember
Interest income recognized	1us-gaap_InterestIncomeRelatedParty / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_NotesReceivableMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_EmployeesMember	4us-gaap_InterestIncomeRelatedParty / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_NotesReceivableMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_EmployeesMember
Parent | Expense allocation of occupancy expenses
Related-party transactions
Expenses		2,316us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty / us-gaap_RelatedPartyTransactionAxis = mc_ExpenseAllocationOfOccupancyExpensesMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_ParentCompanyMember
Parent | Expense allocation of communication, technology and information service expense
Related-party transactions
Expenses		2,745us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty / us-gaap_RelatedPartyTransactionAxis = mc_ExpenseAllocationOfCommunicationTechnologyAndInformationServiceExpenseMember / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = us-gaap_ParentCompanyMember
Moelis Australia Holdings
Related-party transactions
Due from related party					945us-gaap_DueFromRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAustraliaHoldingsPTYLimitedMember
Due to related party	78us-gaap_DueToRelatedPartiesCurrentAndNoncurrent / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAustraliaHoldingsPTYLimitedMember
Moelis Asset Management LP
Related-party transactions
Fee for services	446mc_RelatedPartyTransactionManagementFeeForServices / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAssetManagementLPMember
Due from related party	0us-gaap_DueFromRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAssetManagementLPMember				79us-gaap_DueFromRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAssetManagementLPMember
Investment into the entity controlled by a related party						265us-gaap_EquityMethodInvestments / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAssetManagementLPMember
Income (loss) from equity method investment	2,553us-gaap_IncomeLossFromEquityMethodInvestments / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAssetManagementLPMember
Revenue from Related Parties	$ 742us-gaap_RevenueFromRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAssetManagementLPMember	$ 0us-gaap_RevenueFromRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mc_MoelisAssetManagementLPMember

X

- Definition

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